Various types of digital encoding transducers, for example as shown in U.S. Pat. No. 3,683,368, are in use for a multitude of purposes in process control, research, marketing, public utility and consumer fields. For reasons of economy, safety, environmental, and conservation, it is desirable to obtain data from these transducers via a telephone network, particularly by public utilities measuring water, gas, and electricity consumption by a consumer.
The present invention generally relates to a transponder for transmission of data from digitally encoding transducers over the telephone network without interfering with the telephone service.